I do a daily blessing as well and I do not cast a circle while I am doing it.

You are correct in that there are small things that you do which do not require a circle. For instance, when I am cooking dinner I raise a bit of energy and put it into the food that it will keep us healthy and strong. I don't cast a circle when I'm doing that either.

When I want fast protection just make a light shield around my body, enough for your daily blessings, cooking, gardening ... With a little practice you can instantly raise it. Your thinking is right to me.

you don't have to, i do a daily prayer/blessing in the morning and evening. sometimes when i light an offering of incense i don't cast a circle, just dedicate it and place it on my altar. unless you're planning a ritual and calling your deities to join you, i don't think you need a circle.